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BUG: KCSAN: data-race in snd_seq_check_queue / snd_seq_control_queue

write to 0xffff8881289537e4 of 1 bytes by interrupt on cpu 1:
 snd_seq_check_queue+0x251/0x290 sound/core/seq/seq_queue.c:283
 snd_seq_timer_interrupt+0x228/0x240 sound/core/seq/seq_timer.c:158
 snd_timer_process_callbacks sound/core/timer.c:796 [inline]
 snd_timer_interrupt+0xa7c/0xb50 sound/core/timer.c:919
 snd_hrtimer_callback+0x13a/0x220 sound/core/hrtimer.c:50
 __run_hrtimer+0x154/0x4b0 kernel/time/hrtimer.c:1524
 __hrtimer_run_queues kernel/time/hrtimer.c:1588 [inline]
 hrtimer_interrupt+0x37c/0xa40 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0xa3/0x280 arch/x86/kernel/apic/apic.c:1097
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 sysvec_apic_timer_interrupt+0x80/0xd0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
 preempt_count arch/x86/include/asm/preempt.h:26 [inline]
 check_kcov_mode kernel/kcov.c:163 [inline]
 __sanitizer_cov_trace_pc+0x14/0x60 kernel/kcov.c:197
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0xd5/0xa00 net/batman-adv/network-coding.c:718
 process_one_work+0x3e1/0x9a0 kernel/workqueue.c:2269
 worker_thread+0x665/0xbe0 kernel/workqueue.c:2415
 kthread+0x20d/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff8881289537e4 of 1 bytes by task 14647 on cpu 0:
 queue_access_unlock sound/core/seq/seq_queue.c:370 [inline]
 snd_seq_control_queue+0x4f2/0x550 sound/core/seq/seq_queue.c:734
 event_input_timer+0x1e/0x30 sound/core/seq/seq_system.c:103
 snd_seq_deliver_single_event+0x31b/0x4f0 sound/core/seq/seq_clientmgr.c:638
 snd_seq_deliver_event+0x192/0x4a0 sound/core/seq/seq_clientmgr.c:839
 snd_seq_dispatch_event+0x14c/0x270 sound/core/seq/seq_clientmgr.c:913
 snd_seq_check_queue+0xfe/0x290 sound/core/seq/seq_queue.c:264
 snd_seq_enqueue_event+0x275/0x2b0 sound/core/seq/seq_queue.c:333
 snd_seq_client_enqueue_event+0x206/0x2a0 sound/core/seq/seq_clientmgr.c:974
 snd_seq_write+0x435/0x550 sound/core/seq/seq_clientmgr.c:1093
 vfs_write+0x1df/0x6f0 fs/read_write.c:576
 ksys_write+0xce/0x180 fs/read_write.c:631
 __do_sys_write fs/read_write.c:643 [inline]
 __se_sys_write fs/read_write.c:640 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:640
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 14647 Comm: syz-executor.1 Not tainted 5.8.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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